Photodegradation of o-Cresol in Water by the H₂O₂/UV Process

Abstract

Photodegradation of o-cresol in water has been investigated using hydrogen peroxide as an oxidant along with ultra violet lamps. The synergistic effect of H₂O₂ and UV light was found to be effective to decomposition of o-cresol in water. The effects of wave length of UV light, initial concentration of o-cresol, hydrogen peroxide dose and initial solution pH on photodegradation rate of o-cresol were systematically examined. Degradation of o-cresol with UV-C lamps (wavelength of 254 nm) was more significant than that with near-UV black light lamps (wavelength of 352 nm). The optimal solution pH was around 5 being the natural pH of the solution. The efficiency of o-cresol degradation increased as initial o-cresol concentration decreased. There was the optimal H₂O₂ dose being around 150 mM when the initial o-cresol concentration was 0.93 mM. Based on the experimental results, a kinetic model for the photodegradation of o-cresol by H₂O₂/UV has been developed. The model could simulate the experimental results reasonably.

Key Words: :

• H₂O₂/UV process
• o-Cresol
• Photodegradation kinetics.